tendril, slender, sensitive structure of many climbing plants that by a response to contact (see auxin) supports the plant. Tendrils are modified stems, leaves, or leaf parts or roots. Most young tendrils revolve slowly in their natural growth, as do the growing tips of roots and shoots; the tendrils of different plant varieties may have a consistent tendency to clockwise or to counterclockwise spiraling. The most common kind of tendril (pea, grape) coils around a slender support and then contracts spirally, becoming springy and drawing the plant to the support. The disk-tipped tendril (Virginia creeper, Boston ivy) adheres firmly to brick, stone, or wood, after which it too contracts. For other means of climbing in plants, see climbing plant.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.